bpf2go - Go Packages (original) (raw)

bpf2go

bpf2go compiles a C source file into eBPF bytecode and then emits a Go file containing the eBPF. The goal is to avoid loading the eBPF from disk at runtime and to minimise the amount of manual work required to interact with eBPF programs. It takes inspiration from bpftool gen skeleton.

Add bpf2go as a tool dependency in your project's Go module:

go get -tool github.com/cilium/ebpf/cmd/bpf2go

Invoke the tool using go generate:

//go:generate go tool bpf2go foo path/to/src.c -- -I/path/to/include

This will emit foo_bpfel.go and foo_bpfeb.go, with types using fooas a stem. The two files contain compiled BPF for little and big endian systems, respectively.

Environment Variables

You can use environment variables to affect all bpf2go invocations across a project, e.g. to set specific C flags:

BPF2GO_CFLAGS="-O2 -g -Wall -Werror $(CFLAGS)" go generate ./...

Alternatively, by exporting $BPF2GO_CFLAGS from your build system, you can control all builds from a single location.

Most bpf2go arguments can be controlled this way. See bpf2go -h for an up-to-date list.

Generated types

bpf2go generates Go types for all map keys and values by default. You can disable this behaviour using -no-global-types. You can add to the set of types by specifying -type foo for each type you'd like to generate.

Examples

See examples/kprobe for a fully worked out example.